Cells

Question 1

Properties of Life

Answer 1

order, sensitivity or response to the environment, reproduction, adaptation, growth and development, regulation/homeostasis, energy processing, and evolution.

Question 2

Organisms are highly organized, coordinated structures that consist of one or more cells.

Answer 2

Order

Question 3

Organisms respond to diverse stimuli. Movement toward a stimulus is a positive response, while movement away from a stimulus is a negative response.

Answer 3

Sensitivity

Question 4

duplicating their DNA, genes are passed along to an organism’s offspring. These

Answer 4

Reproduction

Question 5

All living organisms exhibit a “fit” to their environment by natural selection,

Answer 5

Adaptation

Question 6

“steady state” relatively stable internal environment required to maintain life. Two

Answer 6

Regulation/Homeostasis

Question 7

metabolic activities.

Answer 7

Energy Processing

Question 8

The diversity of life on Earth is a result of mutations, or random changes in hereditary material over time.

Answer 8

Evolution

Question 9

Level of organization

Answer 9

atom < molecule < macromolecule < organelles < cells < tissues < organs < organ system < organism < population < community < ecosystem < biosphere

Question 10

a simple, mostly single-celled (unicellular) organism that lacks a nucleus, or any other membrane-bound organelle.

Answer 10

prokaryote

Question 11

Prokaryotic DNA is in the cell’s central part:

Answer 11

Nucleolus

Question 12

a phospholipid bilayer with embedded proteins that separates the internal contents of the cell from its surrounding environment.

Answer 12

The Plasma Membrane

Question 13

of cells that specialize in absorption fold into fingerlike projections

Answer 13

microvilli

Question 14

cell’s entire region between the plasma membrane and the nuclear envelope. comprised of organelles suspended in the gel-like cytosol, the cytoskeleton, and various chemicals

Answer 14

Cytoplasm

Question 15

houses the cell’s DNA and directs the synthesis of ribosomes and proteins.

Answer 15

Nucleus

Question 16

double-membrane structure that constitutes the nucleus’ outermost portion

Answer 16

nuclear envelope

Question 17

semi-solid fluid inside the nucleus, where we find the chromatin and the nucleolus.

Answer 17

nucleoplasm

Question 18

structures within the nucleus that are made up of DNA, the hereditary material.

Answer 18

chromosomes

Question 19

unwound protein-chromosome complexes

Answer 19

chromatin

Question 20

aggregates the ribosomal RNA with associated proteins to assemble the ribosomal subunits that are then transported out through the pores in the nuclear envelope to the cytoplasm.

Answer 20

nucleolus

Question 21

cellular structures responsible for protein synthesis.

Answer 21

Ribosomes

Question 22

“powerhouses” or “energy factories” responsible for making adenosine triphosphate (ATP). oval-shaped, double membrane organelles that have their own ribosomes and DNA.

Answer 22

Mitochondria

Question 23

small, round organelles enclosed by single membranes. They carry out oxidation reactions that break down fatty acids and amino acids. They also detoxify many poisons that may enter the body.

Answer 23

Peroxisomes

Question 24

membrane-bound sacs that function in storage and transport.

Answer 24

Vesicles and Vacuoles

Question 25

microtubule-organizing center found near the nuclei of animal cells.

Answer 25

centrosome

Question 26

“garbage disposal.” Enzymes aid in breaking down proteins, polysaccharides, lipids, nucleic acids, and even worn-out organelles. These enzymes are active at a much lower pH than the cytoplasm's.

Answer 26

Lysosomes

Question 27

a rigid covering that protects the cell, provides structural support, and gives shape to the cell.

Answer 27

cell wall

Question 28

have their own DNA and ribosomes, carry out photosynthesis.

Answer 28

Chloroplasts

Question 29

plays a key role in regulating the cell’s concentration of water in changing environmental conditions.

Answer 29

central vacuole

Question 30

series of interconnected membranous sacs and tubules that collectively modifies proteins and synthesizes lipids.

Answer 30

endoplasmic reticulum (ER)

Question 31

Ribosomes transfer their newly synthesized proteins into the lumen where they undergo structural modifications, such as folding or acquiring side chains.

Answer 31

Rough ER

Question 32

few or no ribosomes on its cytoplasmic surface. functions include synthesis of carbohydrates, lipids, and steroid hormones; detoxification of medications and poisons; and storing calcium ions.

Answer 32

Smooth ER

Question 33

Sorting, tagging, packaging, and distributing lipids and proteins takes place in the

Answer 33

Golgi apparatus

Question 34

diffusion of water through a semipermeable membrane

Answer 34

Osmosis

Question 35

ATP is required to move a substance across a membrane, often with the help of protein carriers, and usually against its concentration gradient.

Answer 35

Active Transport

Question 36

difference in concentration of a substance across a space.

Answer 36

concentration gradient

Question 37

movement of particles from an area of higher concentration to an area of lower concentration.

Answer 37

Diffusion

Question 38

contains both a hydrophilic and a hydrophobic region.

Answer 38

amphipathic